A+ A- Aa Weatfield Inc. applies overhead to production at a predetermined rate of 90% based on direct labor cost. Job No. 170, the only job still in process at the end of March, has been charged with manufacturing overhead of $8,100. What was the amount of direct materials charged to Job 170 assuming the balance in Work in Process inventory is $30,000? 01) $30,000. 02) $12,900. 03) $9,000. 04) $ 8,100